DE1758716A1 - Haematite iron grain or powder and process for its manufacture - Google Patents

Description

DlPL-ING. HELLMUTH KOSEL DIPL-ING. HORST ROSE DIPL-ING. PETER KOSEL PATENT LAWYERS

3353 Bad Gandersheim, ^{July 26th} Braunschweiger Strasse 22

Telephone: (05382) 2842

Telegram address: Siedpatent Bad Gandersheim

POTIDHBS ET "GBEKTAIIiLES METALLIQUES
Patent application dated July 26, 1968

POUDRES ET GREHAILLES METALLIQUES 2, rue Alfred de Vigny
Paris, France ''

Hematite iron grain or powder and method of making it __ _{-— ______}

The invention relates to a grain or powder made of hematite iron and to a method of manufacture of such a grain or powder.

There are already different types of metallic grain, in particular cast iron grains and steel grains, for Polishing, grinding, cutting, drilling, pickling, cleaning and ■ tf-eiben has been proposed.

The grains of hematite iron of a known type wise, although they are less fragile or brittle than the grains of phosphorus pig iron, nevertheless have the disadvantage that they have a lower hardness than the latter Have grains, on the order of 600 to 700 degrees of Brinell hardness.

The invention is based on the object, while enabling industrial production, a grain or To create powder from hematite iron, which has a greater hardness than the known grains, namely a hardness of at least 800 degrees of Brinell hardness, but less fragile or spotty than the grains described made of phosphorus pig iron.

209809/0521 2598/1 Rö / ed.

The grain or powder of hematite iron according to the invention is characterized in that it is from 2.00 to 3.80% by weight carbon, 0.50 to 1.80% by weight Contains silicon, 0.20 to 2.00% by weight of manganese and at most 0.15% by weight of sulfur and phosphorus. the The concentration of sulfur and phosphorus in the grain should therefore be less than or equal to a proportion of 0.15% by weight be.

The grain or powder composed according to the invention has two advantages over the known one Grain made of phosphorus pig iron on the one hand that it has a much greater hardness than this known grain and on the other hand, has a much lower fragility or brittleness due to the hematite.

P The well-known grains of hematite iron show how

has already been carried out, a hardness between 600 and 700 degrees of Brinell hardness. Such a well-known one Grain is manufactured by a known method in which a jet of an overwhelming fluid, for example a jet of water, is melted onto a jet Metal is directed so that the metal is pulverized into fine droplets, which are collected in a container filled with water when touched the grains solidify.

The method according to the invention achieves that the metal grain or powder produced in this way is given a hardness of at least 800 degrees of Brinell hardness. This method is characterized in that after carrying out, for example, the production step described above, the grain or powder under non-oxidizing Atmosphere brought to a temperature of 800 ° G and then exposed to ambient temperature, namely expediently by immersing the heated grain or powder in water at ambient temperature.

The temperature increase in the heating phase is expedient at a rate below 100 ° C / min causes. In further training, the grain or powder is expediently at least in the heating phase

- 2 -
209809/0521

Maintained at maximum temperature for 5 minutes.

It is of course necessary in the course of the

t. . . ■ ■ ■

Temperature rise any local overheating or to avoid untimely overheating affecting the physical and / or change chemical properties of the grain or powder.

Research has shown that it can be used evenly Heating the grains or the powder is advantageous, according to the invention the temperature treatment or To carry out heating in a continuously operated rotary flame furnace, its operating conditions and dimensions are chosen so that the individual Whole grain quantity or powder grain quickly, heated evenly and without the risk of overheating. ™

The grain or powder of hematite iron, which under Obtained in these conditions is much tougher and much less fragile or brittle than one Grain made from the well-known phosphorus pig iron. The grain or powder according to the invention is therefore for all such Particularly suitable applications where a very hard, but not fragile or brittle grain is required.

- 5 - ■

BATH

209809/052 1

Claims (6)

Claims 1. Grain or powder made of hematite iron, thereby indicates that it contains 2.00 to 3.80 weight- ^ carbon, -0.50 to 1.80 weight- 96 siliconJ ^ 0.20 to 2.00 ^ weight- ^ manganese and at most 0.15 weight- ^ Contains sulfur and phosphorus. 2. Method of making a grain or powder according to claim 1, characterized in that after Her- » position of the iron grain or powder the grain or powder brought to a temperature of .800 ° C in a non-oxidizing atmosphere and then exposed to ambient temperature will. 3. The method according to claim 2, characterized in that that the grain or powder is immersed in water at ambient temperature after heating. 4. The method according to claim 2 or 3, characterized in that the temperature rise in the heating phase causes at a rate below 100 ° C / min will. 5. The method according to claim 2, 3 or 4, characterized in that the grain or powder is held in the heating phase for at least 5 minutes at the maximum temperature will. 6. The method according to claim 2, 3, 4 or 5, characterized in that the grain or powder in one continuously operated rotary flame furnace is heated while avoiding local or untimely overheating. Patent attorney · Dipl.-ing. Hellmuth Kot! Dipl.-Ing. H ο r s t R Ö s DipUkig. Peter Kos ·! 209809/0521